Valve-stem stretcher.



-w. E. SMITH.

VALVE STEM STRETCHER.

APPLICATION FILED APR. 7, 1914.

1,175,021. Patented Mar. 14,1916.

amwwlio'o WILLIAM E. SMITH, OF JOHNSTOWN, PENNSYLVANIA.

VALVE-STEM sran'rcnnn.

Specification of Letters Patent. Patented E1 313 14 19152 Apnliea'tion filed April 7, 1914. Serial No. 830,259.

To all whom it may] concern:

' Be it known that 1, WILLIAM E. SMHH, a citizen of the United States, residing at Johnstown, in the county of Cambria and State of Pennsylvania, have invented new and useful Improvements in Valve-Stem Stretchers, of which the following is a specification.

This invention relates to valve stem stretchers, the object in view being to provide a device for elongating the stem of a valve when said stem becomes worn at its extremity and sufficiently short to be unfit for further use.

fit the above and other objects in view, the invention consists in the novel construction, combination and arrangement of parts, as will'be hereinafter more fully described, illustrated and claimed.

In the accompanying drawings :Figure 1 is a perspective view of the stretching de vice of this invention. Fig. 2 is a cross section through the same in line with the key or guide pin. Fig. 3 is a central longitudinal section through the device.

When the lower end of the stem of a valve wears off from being tapped by the lower tappet or push rod, a gap is caused between the extremity of the valve stem and the tappet or push rod which causes a material loss of power by reason of the valve not opening at the proper time or fully and also causes a clattering noise of the valve. There is no practical way of eliminating this trouble except to lengthen the stem of the valve, even a new valve failing to remedy the trouble for the reason that it is seldom of suiticient length on account of the fact that the lower tappet or push rod. is also worn off on its abutting end and the new stem will not reach it. By means of the invention to be described, it is a comparatively simple matter to elongate or draw out the stem of the valve so as to render the same of the necessary length.

The device of this invention comprises a holder 1 which is adapted to be clamped in an ordinary bench vise and which has an open center 2 for the purpose of exposing a portion of the valve stem in order that it may be heated preparatory to the stretching operation.

The holder 1 is provided with an extending neck 8 which is cylindrical in cross section and externally threaded at 4 to receive a nut 5.

Surrounding the outer portion of the neck 3 is a stretching element 6 shown in the form of a sleeve which is slidable longitudinally of the neck and is adapted to bear against the body of a valve, 7 designating such valve body and 8 the valve stem which is provided as shown with a hole 9 near the end opposite the valve body 7 to receive the usual pin which confines the valve seating spring in place thereon.

The sleeve 6 is prevented from rotating around the neck 3 and imparting a like movement to the valve body and stem by means of a key or pin 10 shown in the form of a screw inserted in a threaded socket 11 in the neck 6, said key extending through and working in a groove 12 running lengthwise of the sleeve 6 as clearly shown in Fig. 3. The body of the device is also formed with a central longitudinal here to provide the valve stem receiving holes 13 and 1%.

In operation, the holder 1 is, as above indicated, clamped in a vise. The nut 5 is then turned toward the base of the neck 3 and the valve with its attached stem is then inserted in the holder in the position illustrated in Figs. 1 and 3, a pin being then inserted through the hole 9 in the valve stem to prevent longitudinal movement of said stem. The exposed portion of the valve stem is then heated by any suitable means such, for example, as a blow torch until a red heat is reached. By means of a wrench the nut 5 is then turned so as to advance the sleeve 6 against the valve body 7. A half or three-quarter turn or more may be imparted to the nut 5 in accordance with the amount of elongation required for the valve stem 8.

It is good practice before the valve is removed from the motor to ascertain the amount of elongation required, the nut 5 being turned accordingly. Should the stem, however, be too greatly elongated, it is a comparatively small matter to dress off the extremity of the stem until it is of exactly the proper length. The device is of such simple and economical construction that it may be manufactured at low costand will pay for itself in a very short period of time.

What I claim is l. A device for lengthening the stem of a valve, comprising a holder formed to receive the valve stem, means for holding the valve stem against longitudinal movement adjacent to the extremity thereof, and

stem stretching means on said holder adapted to operate against the valve body.

' 2. A device for lengthening the stern of v on said holder adapted to operate against the valve body.

3. A device for lengthening the stem of a valve, comprising a holder formed to receive the valve stem, means for holding the valve stem against longitudinal movement adjacent to the extremity thereof, and stem stretching means on said holder embodying a nonrotary pressure element adapted to bear against the valve body, and a rotary element having a threaded engagement with the holder and contacting with said pressure element.

5. A device for lengthening the stem of.

a valve, comprising'a valve stem holder constructed to prevent longitudinal movement of the valve stem and expose part of said stem to be heated, and means adapted to operate against the valve body to elongate the stem.

In testimony whereof I aiiix my signature in presence of two witnesses.

l/VILLIAM E. SMITH.

Witnesses AMBRosn BERKEBILE, M. R. BRENNAN.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of ratents,

Washington, D. G. i 

